Self-priming centrifugal pump



July 9, 1957 C. l. ALONGENECKER SELF-'PRIMING CENTRIFUGAL PUMP Filed April l2, 1951 3 Sheets-Sheet l INVENTOR. GHA/'PLES LLOIVGENEGKEH ATTORNEY July 9, 1957 c. l. LONGENECKER 2,798,439

SELF'-PRIMING CENTRIFUGAL PUMP 5 Sheets-Sheet 2 Filed April l2, 1951 FIGS.

INVENTOR. GHRLES [LONGENEGKEH BY l ATTORNEY July 9, 1957 c. 1. LoNGENl-:cKr-:R 2,798,439

SELF-PRIMING CENTRIFUGAL PUMP s sheets-sheet s Filed April 12. 1951 FIGB.

FIG. Il.

INVENTOR. HRLS l LONGENEGKER BY 'W4/' CMM ATTORNEY United States Patent SELF-PRllVIING CENTRIFUGAL PUMP Charles I. Longenecker, Wauwatosa, Wis., asisgnor to Chain Belt Company, Milwaukee, Wis., a corporation of Wisconsin Application April 12, 1951, Serial No. 220,611

4 Claims. (Cl. 1037-113) This invention relates generally to centrifugal pumps of the self-priming type, and more particularly to a unitaryself-primin-g pump of improved and simplified design.

A general object of the present invention is to provide an improved self-priming centrifugal pump of simple and rugged construction.

Another object of the invention is to provide an improved adjustable peeler for a centrifugal pump of the self-priming type.

Another object is to provide an improved arrangement whereby a peeler movably mounted within a self-priming centrifugal pump may be adjusted from the outside of the pump housing.

According to this invention, an improved centrifugal pump of the self-priming type is provided with an adjustable peeler that is movably mounted entirely within the pump casing and is secured in adjusted position by securing means rotatably mounted in the wall of the casing and operative from the exterior thereof. The pump housing is preferably in the form of an integral casting constituting an impeller chamber and a superimposed priming water chamber, interconnected by integrally formed substantially parallel discharge and priming passages. The movably mounted peeler is disposed to cooperate with the periphery of the pump impeller at a position between the discharge passage and the priming water passage. The peeler may be in the form of a bar presenting a chisel-like end to the impeller and may be mounted for either sliding or pivotal movement toward or from the impeller periphery. A set screw threaded through the housing wall or equivalent fastening means may be used to retain the peeler in adjusted position, the outer end ofthe `screw being covered by one edge of the pump side plate or left exposed as may be desired. For moving the peeler within the housing there may be provided an actuating shaft rotatably mounted in the housing wall and fitted with a cam or eccentric element to engage the peeler. The pump cover plate may be bolted to the housing or it may be made more readily detachable by providing `locking arms thereon for engaging cooperating `lugs on the housing. To facilitate turning the impeller manually the cover plate may be provided with a suitable impeller engaging tool for use when the plate is detached. j

The foregoing and other objects of this invention will become. more fully apparent as the following detailed description of exemplary embodiments thereof is read in conjunction with the accompanying drawings, in which:

Figure l is a view in front elevation of a self-priming centrifugal pump embodying features of the present invention, parts having been broken away to better reveal internal details;

Fig. 2 is a View in rear elevation of the pump structure shown in Fig. 1 with parts broken away to reveal the pump interior; i

2,798,439 Patented July 9, 1957 Fig. 3 is a view in vertical section taken axially of the pump on the planes represented by the lines 3--3 in Figs. l and 2;

Fig. 4 is a fragmentary detailed view taken through the improved peeler of the pump on the plane represented by the lines 4-4 in Figs. 2 and 3;

Fig. 5 is a view in front elevation of the pump impeller as partly shown in Fig. 1 illustrating another means for retaining the impeller on the end of the shaft;

Fig. 6 is a fragmentary View in perspective of part of the impeller and shaft as shown in Fig. 5, together with part of a modified cover plate provided with im peller engaged tool elements;

Fig. 7 is a fragmentary View infront elevation similar to Fig. 1 but showing a modified embodiment of the mvention;

Fig. 8 is a fragmentary detailed view of the moditied structure taken in horizontal section on the plane represented by the line 8 8 in Fig. 7;

Fig. 9 is another view in front elevation similar to Fig. l but showing a pump embodying a further modification of the invention;`

Fig. 10 is a view in horizontal section taken on the plane represented by the line 10--10 in Fig. 9; and

Fig. 11 is an enlarged fragmentary detailed view of the modified peeler taken in Vertical section on the plane represented by the lines 11-11 in Figs. 9 and l0. l Referring more specifically to the drawings and particularly to Figs. l, 2 and 3 thereof, the pump there shown as a preferred embodiment of the present invention is a centrifugal pump of the recirculating or self-priming type, 1ts housing being of a unitarily cast structure, although it is to be understood that other structures taking various forms may be utilized for practicing the invention without departing from the spirit thereof as defined in the claims.

As shown in Figs. 1 and 2, the pump embodying the present invention comprises essentially a unitary housing or casing 10 that is preferably an integral casting of iron or other suitable material and that constitutes the body or frame of the pump. Formed integrally Within the casing 10 between its side Walls is an impeller space or working chamber 11 in the form of a spiral or `volute and adjacent to it is a concentrically arranged intake chamber 12 of scroll shape separated therefrom by a diaphragm or partition 13 that has formed centrally thereof an inlet opening or port 14 as shown in Fig. 3. .Above the impeller chamber 11 and superimposed thereon is an inice `tegrally formed priming water or recirculating chamber 16 into which water is discharged from the impeller chamber through an interconnecting vertically disposed discharge passage 17 constituting a tangential extension of the impeller chamber volute. The intake chamber 12 is likewise provided with an integrally formed tangential intake passage 18 extending horizontally along its upper side and through which water is drawn into the pump to be discharged through the vertical passage 17. As shown in Figs. l, 2 and 3, the priming water chamber 16 is provided at its top with a threaded discharge opening that receives a nipple 21, to which is screwed a T connection 22 having a side outlet or discharge opening23 that may be connected to a pipe or hose line (not shown) and having an upper priming opening 24 that is ordinarily closed by a plug 25 that also constitutes a lifting ring for handling the pump. In starting the pump initially, the plug 25 is removed and some of the liquid to be pumped is poured through the opening 24 into the chamber or reservoir 16 for which it ilows into the impeller chamber 11 to prime the pump.

As shown in Fig. 3, the part of the housing forming the impeller chamber 11 is provided at the side opposite from the inlet opening 14 with an impeller admitting opening 28 through which an impell-er or runner 29 may be introduced into the chamber 11, the opening 28 being closed by a cover or side plate 30 that is` secured to the housing by a circle of retaining stud bolts 31. The impeller 29 is threaded on the end of and rotatably supported within the volute chamber 11 by means of a shaft 33 that extends centrally through the intake opening 14 and through a shaft receiving opening 34 in the housing wall at the side of the intake chamber 12 opposite from the inlet opening 14. To prevent leakage of liquid along the shaft 33 through the opening 34, there is provided a suitable sealing or packing gland 35 at the point where the shaft passes through the side of the housing. The shaft 33 may be connected to or 'constitute part of a driving apparatus here represented by one end of an electric motor 36 to which the pump housing 10 i's in this instance attached by suitable bolts 37.

When the motor 36 is energized to operate the pump, the impeller 29 is turned in the direction indicated by the arrow in Fig. 2 in such a manner that rearwardly curved vanes or blades 41 on the impeller disk engage the water or other liquid which was introduced through the priming opening 24 and throw it by centrifugal force outward and upward through the tangential passage 17 together with entrained air which is drawn in through the intake opening 18 in building up suction to ,prime the pump. The water thrown upward through the vertical passage 17 into the separating space inthe priming chamber 16 separates from the air therein and drains back through an adjacent priming passage 43 at the bottom of the chamber that is circumferentially spaced from and lies in parallel relationship with the discharge passage 17, and that opens into the impeller chamber 11 posteriorly thereof, whereby the water may reenter the impeller 29 to entrain additional air in continuing the priming process.

From the foregoing description of the arrangement of elements and construction of the housing it will be observed that a minimum of space is required through the utilization of an impeller chamber of a width just sutlcient to receive the impeller and the superimposing of a priming chamber of substantially greater width above the impeller chamber, whereby the capacity of the priming chamber relative to the capacity of the impeller is properly balanced. With the inlet scroll disposed below a portion of the priming chamber, in the manner shown, the over-all width of the housing is not increased, and it is possible to utilize an integral cast housing of compact design and minimum weight.

In order that the priming water may be caused to recirculate freely into the impeller chamber through the priming passage 43, as much water as possible is deected from the periphery of the impeller 29 into the discharge passage 17 ahead 4of the priming passage 43. This is effected by means of a peeler of the general type disclosed in prior U. S. Patent No. 1,989,061 for increasing the priming efficiency.

In the present construction, an improved adjustable peeler 44 is movably mounted in the housing between the discharge passage 17 and the priming passage 43 and in effect constitutes a guide vane forming part of the inner side wall of the passage 17. As shown in Figs. 1, 2, 3 and 4, the peeler 44 may be in the form of a rectangular blade or plug of material such as steel that is sharpened at one end to a straight sharp edge or chisellike point and is disposed vertically in the housing 10 with its pointed end lowermost and adjustably positioned adjacent to the periphery of the impeller 29, the arrangement being such that the peeler 44 engages water and entrained air rotating with the impeller 29 and diverts it from the impeller periphery into the passage 17. As shown, the peeler 44 is in this instance pivotally suspended in the housing 10 upon a pivot stud or pin 45 in such a manner that its lower pointed end is freeto swing toward or from the impeller periphery ufor a'djutrfleltq As best shown in Figs. 3 and 4, the pivot pin 45 may be in the form of a cap screw or the like threaded through the front wall of the casing 10 and provided with a lock nut 46 to retain it in position. Preferably a washer 47 of copper or like suitable material is interposed between the lock nut 46 and the surface of the housing 10 as a packing to seal the opening against leakage from the interior of the pump.

By reason of its pivotal movement, the peeler blade 44 may be adjustably positioned to bring its pointed end as near as practicable to the periphery of the impeller 29 for enhancing its effectiveness in diverting water therefrom into the discharge passage 17. After the peeler 44 has been suitably adjusted, it may be locked in adjusted position by a securing or fastening means which in the structure shown is in the form of a retaining set screw 49 that is threaded through the wall of the housing 10 in position to engage the vpeeler near its lower end for forcing it against the inner wall 13 of the impeller chamber 11 to retain it in adjusted position. As best shown in Fig. l, the locking set screw 49 is threaded through a portion of the wall of the housing 10 adjacent to the opening 28 that has been faced to form an encircling annular surface 50 to receive the cover plate 30, the arrangement being such that when the cover plate is in position to close the opening 28 the plate also covers the outer end of the set screw 49 to protect it from inadvertent misadjustment. A suitable packing ring 51 is interposed between 'the cover plate 30 and the faced surface 50 of the housing to prevent leakage in the region of the cover plate, the packing serving also to prevent leakage around the locking set screw 49.

In adjusting the .peeler 44, the cover plate 30 is removed from Ithe housing, after which the set screw 49 may be loosened and the peeler point moved to the desired position relative to the impeller periphery while under observation through the impeller admitting opening 28. The set screw 49 is then tightened to hold the peeler in adjusted position and 4the cover plate is replaced. lf desired, two set screws may be employed in series in the same threaded opening, with one serving to lock the other to prevent accidental loosening.

To remove the peeler 44 for repair or replacement, the coverplate 30 is rst removed and the impeller 29 is then withdrawn from the end of the shaft 33. An annular wear plate or backing plate 52 that is secured to the partition 13 behind the impeller 29 by screws 53 is likewise removed through the opening 28 after withdrawing the screws which secure the plate to the partition. AThe retaining set screw 49 and the lock nut 46 may ythen be loosened and the stud bolt 45 unscrewed from the housing, whereupon the peeler 44 may be removed through the opening 28.

l In reassembling the Pump, the new or repaired peeler 44 is insented into its position in the housing and the stud bolt 45 constituting the suspension pivot is replaced and locked in position by the lock nut 46 and packing washer 47, as shown in Figs. 3 and 4. The annular wear plate 52 is then introduced into the chamber 11 in position to encircle the inlet port 14 and ispheld in place by replacing the screws 53. The impeller 29 is fthen replaced within the chamber 11 by securing it on the end of the shaft 33. With the parts thus reassembled in the chamber, the new peeler is then adjusted relative to the impeller periphery as previously explained and the set screw 49 tightened to hold it in adjusted position, after which the packing ring 51 and cover plate 30 are replaced to close the opening 28 and cover the set screw 49 as previously explained.

By mounting the peeler 44 for adjusting movement relative to the impeller periphery as herein `'described and securing it in adjusted position as by the locking set screw 49, there has been provided through the present invention a compact and readily adjustable peeler arrangement that tits into the housing of a centrifugal pumpV without interfering with other features thereof, and without requiring :spaanse` that Ithe housing be enlarged or otherwise materially moditied to accommodate the adjustable peeler. By reason of its simple and compact construction, the adjustable peeler of this invention constitutes a material improvement over previously known peelers, its compact arrangement being particularly advantageous in pumps of the smaller sizes, where space is at a premium and wherein it was previously necessary to enlarge the housing to accommodate arrangements for adjusting the peeler.

Although the adjustable peeler of Figs. 1, 2, 3 and 4 is shown as being locked in adjusted position by the set screw 49 that is covered by the edge of the cover plate 30, it is to be understood that by slightly modifying the structure, a suitable locking set screw may be applied to the peeler by threading it through a portion of the housing not covered by the plate 30. In this event it is desirable to use a somewhat longer set screw and to provide the set screw with a locking nut and packing washer similar to the nut 46 and washer 47 of the stud bolt 45 to prevent leakage, as shown in Fig. 11 and described hereinafter in connection therewith.

When the pump is started, as previously explained, the water thrown into the priming chamber 16 is separated from entrained air therein and flows back through the priming passage 43 into the impeller chamber 11 where it is mixed with air drawn in through the intake opening 18 and serves to eject the air through the discharge passage 17. The peeler 44, being adjusted in close proximity to the periphery of the impeller, serves to deflect the water and entrained air from the impeller in order to provide space for the reentry of water through the priming passage 43 to mix with the air in the impeller chamber. This process continues until all the air is evacuated from the intake passages and the liquid to be pumped is drawn into the pump. After the impeller chamber 11 has been completely filled with liquid, there is no longer space for liquid to ow downwards through the priming passage 43 into the impeller chamber and since some liquid is thrown tangen tially from the impeller beneath the passage 43 the flow therethrough is actually reversed and serves to supplement to a small extent the ilow through the discharge passage 17.

As best shown in Fig. l, the intake passage 18 may be provided with an intake connector 55 including a check valve arrangement, that is bolted to the housing 10 and that is adapted to elfect a connection with a suction pipe 56 or the like. The connector structure 55 is provided with an inwardly extending sleeve 57 fitted with a circumferential O ring 58 that forms a seal between the periphery of the sleeve 57 and the interior of the intake passage 18. As shown, the sleeve S7 terminates in a downwardly and inwardly sloping surface forming an angularly disposed inner face or seat that is engaged by a flap valve or check valve 59 of weighted exible material. The ilap valve 59 is secured at the top of the structure 55 by a screw 61 and is free to deflect inwardly and upwardly to admit water from the pipe 56 into the intake passage 18, the arrangement being such that the valve flap 59 closes downwardly upon the sloping seat in the event of a return flow to prevent the priming water from being siphoned out of the pump housing into the pipe 56.

As previously mentioned, the impeller 29 is in this instance threaded on the end of the driving shaft 33, the shaft being provided with external screw threads 63 for this purpose, as shown in Fig. 3. The impeller 29 is likewise provided with complementary internal screw threads 64 and presents in its outer face a transverse slot 65 that is shaped to receive the end of a suitable actuating instrument such as a piece of bar stock that may be used in a manner similar to a screw driver for screwing the impeller onto the shaft. As a matter of convenience, a suitably shaped lug 66 may be formed integrally with the cover plate in such a manner that it is always available for use instead of a bar as an instrument for removing` `or `replacing the impeller.

As previously explained, the packing gland 35, through which the driving shaft 33 enters the pump housing, is mounted in the outer wall of the intake compartment 12. Since during normal operation of the pump the intake compartment is subjected to suction from the pump impeller rather than positive pressure, there is no tendency for abrasive material carried by the liquid being pumped to be forced between the shaft and the packing 35, and the packing is therefore less liable to damage than it would be if it were operating under pressure of the liquid being pumped. Consequently the packing lastsy longer and is more readily maintained in tight engagement with the shaft to prevent inward leakage of air, which might otherwise destroy the vacuum at the pump intake.

In the modification of the invention shown in Figs. 7 and 8, the improved adjustable peeler is in the form of a horizontally disposed bar or plug 74, having one end positioned to constitute part of the inner side of the discharge passage 17 with its lower edge pointed to constitute the peeler blade and being pivotally mounted at its other end on a pivot pin 75 that is disposed substantially in the vertical medial plane of the pump housing. By this arrangement, the end of the peeler 74 adjacent to the discharge passage may be raised or lowered to move its lower pointed peeler edge away from or toward the periphery of the impeller 29. As shown, the peeler 74 is provided above its pointed end with a slot 76 that engages an eccentric pin or cam element 77 on the inner end of an actuating shaft 78 that is provided with external screw threads and is rotatably mounted in a threaded opening extending through the front wall of the housing 10 above the edge of the cover plate for rotation in adjusting the peeler. Upon turning the threaded shaft '78 by means of a screwdriver or the like, the eccentric pin 77 is caused to operate within the slot 76 in a manner to raise or lower the peeler 74, whereby the relationship of its lower pointed end to the periphery of the impeller may be adjusted. After the position of the peeler has been thus adjusted, the shaft 78 may be locked in position by tightening a lock nut 79 threaded thereon. To prevent leakage, a washer 80 of copper or the like is preferably interposed between the lock nut 79 and th surface of the housing.

Because of the fact that the modied peeler 74 extends horizontally, it lies directly beneath and across the path of the priming water passage 43, as show n in Fig. 7. In order that the peeler may not interfere with the flow of priming water, it may be provided with a vertically disposed transverse passage 81 that is aligned with and constitutes an extension of the priming water passage 43 leading radially toward the periphery of the impeller 29. Although the passage 81 is illustrated as passing through the interior of the peeler 74, as best shown in Fig. 8, it is to be understood that the passage might be formed in one side of the peeler by way of a recess such as a notch or groove therein. Furthermore, the notch or groove may be formed in either or both sides of the peeler or the housing may be correspondingly notched or grooved adjacent to the peeler to bypass the priming water around it.

This modification of the invention is further provided with an improved form of impeller cover plate or side plate that is especially adapted to be removed and replaced readily without the use of tools. As shown in Figs. 6, 7 and 8, an improved cover plate 82 is so arrangedthat its periphery tits within the impeller-admitting opening 2 and is provided about its edge with a circumferential groove that receives an O ring 83 which serves as a seal between the outer periphery of the cover plate and the inner surface of the opening 28 to prevent leakage` therebetween. While providing an adequate seal, the O ring 83 permits the cover plate to be inserted into the opening 28 without difficulty and allows it to be turned therein. Tosecure it in position, the plate 82 is provided on its outer surface with a pair of radially extending diametrically opposed locking arms 84, each provided at its outer end with a tangential notch 85, the notched ends of the arms forming hook-like elements extending beyond the periphery of the plate 82 and disposed with their open sides facing in the same angular direction. To secure the plate in position on the housing i after it is inserted in the opening 28, it is turned in the direction of the arrow to bring the notches 35 in the arms into envagement with the Shanks of headed retaining studs or pins 86 projecting from the housing at opposite sides of the opening 28. The direction of rotation of the cover plate 82 for locking it is preferably the same as the direction of rotation or" the impeller 29, as indicated by the arrow, in order that frictional forces acting upon the cover when the pump is operating will tend to tighten rather than loosen the engagement of the hooks with the pins Sti. Furthermore, the pressure exerted upon the cover plate by the liquid being pumped tends to force the plate outwardly and forces the ends of the arms 84 into vtight frictional engagement with the heads of the retaining studs. f

The threaded connection between the impeller 29 and the shaft 33 shown in Fig. 3 is especially adapted for use in pumps driven lby gasoline engines or the like which rotate in only one direction, the direction of rotation being Selected to turn the shaft threads 63 into the impeller threads 6d. However when a pump of this type is driven by an electric motor, there is always the possibility that through improper electrical connections or errors in switching the motor may be caused to operate in the wrong direction, and this might result in unscrewing the shaft from the impeller with consequential damage to the pump. To obviate this possibility, in pumps to be driven by electric motors the impeller is preferably keyed to the shaft in the manner best illustrated in Figs. and 6. In order that `the impeller may be readily removed from and replaced on the shaft, the shaft receiving opening in the impeller is relieved or enlarged at the keyed side thereof as indicated by the clearance 87, the other side being bored concentric and drawn into tight centering engagement with the shaft by the Wedging action of a key 8S. As shown, the key SS is driven into complernentary key seats in the shaft and the impeller respectively. As best shown in Fig. 6, the key 8S is provided with -a head or lug S9, by means of which it may be engaged by a suitable tool to withdraw it from the key seats, thereby releasing the impeller 29 so that it may be removed from the end of the shaft 33.

Euring cold weather the impeller 29 on a pump of this nature may become frozen to the pump casing through the freezing of moisture which remains in the casing after the pump has been drained. In this event it is necessary to free the impeller in order to start the pump, and for this purpose a pair of diametrically opposed slots or grooves 91 may be provided in the impeller hub to receive an actuating instrument of the screw driver or Spanner type. rlhe grooves 9i constitute abutments for turning the impeller, there being no other part of the rotating structure exposed for engagement to turn it.

Suitable means may be provided conveniently for engaging the slots 9i, in the form of a bifurcated instrument presenting a pair of `lugs 92. formed integrally with and projecting outward from the center of the cover plate S2, as shown in Figs. 6, 7 and 8. The lugs 92 are spaced to straddiethe end or" the shaft 33 for engagement with the slots 9i, the arrangement being such that when the cover plate S2; is removed from 'the housing and reversed to engage the lugs 92 in the slots gli, the cover plate may h e grasped in the manner of a hand wheel t'o turn the impeller for freeing it for rotation within the housing. The cover plate may then he replaced in position the motor energized for operating the pump in the normal manner. Qbviously ythe lugs 92 on the cover plate may be adapted for use with a slotted impeller -of |the type shown in Fig. 3 vfor screwing it onto or unscrewing it'from the end of the threaded shaft.

A modified instrument for effecting rotation of the impeller 'is shown formed integrally on a cover plate 94 of another embodiment of the pump that is illustrated in Fig. 9. As there shown, the modified actuating instrument is arranged totft over the end of the shaft 33 and engage the `key `88, the sides of which constitute the force receiving abutments, theslots or grooves 91 being then unnecessary. This modified instrument is in the form of an integrally cast lug 95 projecting axially outward from the lower part of the cover plate 94 and presenting a shaft receiving opening 96 disposed radially of the cover plate.

In the event that it becomes necessary to free the irnpeller, the cover plate 94 may be turned clockwise to disengage the locking arms Sl'from the retaining studs 86 and the cover then withdrawn from the opening 28. The cover plate 94 is then presented edgewise to the opening 28 and the lug 95 disposed to ft the shaft receiving opening 96 over the end of the shaft 33. A slot or notch 97 in the lug 95 is arranged to fit over and engage the key 88 at opposite sides, whereupon the cover plate may be used in the manner of a socket wrench to turn the impeller in either direction.

After the impeller has been freed, the cover plate is withdrawn from the shaft and replaced in the opening 28. The plate is then turned counter-clockwise to lock the arms 84 to the studs S6. To tighten the plate in position,'the projecting lug 95 may be utilized as an abutment that may be struck with a hammer or the like to seat the notches 85 on the 'studs 86. Likewise in removingthe cover, the lug' 95 ymay be struck on the other side to disengage-the notches 85 from the studs 86 and turn the cover in clockwise direction for releasing it.

In the embodiment of the invention shown in Figs. 9, 10 and l1 there is employed a modified peeler 104 which is in the form -of a Icylindrical bar that may be of non-corroding material such as bronze, and that is vertically disposed inthe pump housing 10 between the discharge passage 17 and the priming water passage 43 in a position similar to that of the bar 44 shown in Figs. l to 4. vAs shown, the lower.'end of the modified peeler 104 is sharpened to form a straight transverse chisellike edge that lies adjacent to the periphery of the impeller 29 in ksuch fa manner that the leading face thereof constitutes part of the inner wall of the discharge passage 17 and operates asa guide vane to deflect water from the periphery of the impeller in a manner to divert it into the discharge passage. The cylindrical peeler bar is movably mounted in the housing 10 for vertical sliding adjustment therein toward or from the impeller periphery and the pointed end of the peeler is ordinarily positioned as nearly Vas practicable to the periphery of the impeller. As best shown in Fig. 11, the peeler bar ris held in adjusted position by the clamping action of a set screw 105 that is threaded through the front wall of the housing, the set screw being provided with a lock nut 106 Yand a packing washer 107 which function to lock .the screw in clamping position and to prevent leakage alongits threads. lf desired, the peeler bar 104 may be provided with a peeling point or blade at each end in order that by Vreversing the position of the bar a new peeling edge may be presented after the Ledge first used has become dulled.

As shown, the peeler bar 104 is slidably supported within the housing by means of an inwardly projecting lug or abutment 109 through which there has been drilled a vertical cylindrical bore 110 of suitable size to receive the cylindrical peeler bar 104 with a sliding it. As shown in Fig. 9, the drilled bore of the opening 110 is directly beneath van outlet opening 111 inthe top of the pump housing 10, the outlet being displaced to the right side of the housing in this instance, as shown, in order to align it with the discharge passage 17 and to permit the entry of fa drill through the Outlet to drill the opening 110. To assist in guiding the discharged liquid into 19 the outlet opening 111 there is provided within the priming water chamber 16 a curved baiewall 112 that extends from the front to the back of the chamber between the peeler bore 110 and the priming water passage 43 in a manner to form an extension of the inner wall of the discharge passage 17.

The position ofthe peeler bar 104 is ordinarily adjusted while the cover plate 82. is detached from the housing and may be accomplished conveniently by placing a measuring shim of suitable thickness between the edge of the peeler blade and the periphery of the impeller to provide the desired clearance therebetween. The locking set screw 105 is then tightened and the measuring shim removed.

To assist in the adjusting operation there is also provided an eccentric shaft 115 which is threaded through the front face of the housing above the set screw 105 and is provided at its inner end with an eccentric pin or cam element 116 that engages a circumferential groove 117 in the peeler bar. By turning the threaded shaft 115 by mans of a screw driver or the like, the cam element 116 is caused to operate upon the sides of the groove 117 in a manner to raise or lower the peeler bar in 'effecting the desired adjustment. The threaded shaft 115 may then be locked in position by tightening a lock nut 118 against a packing washer 119 as previously described. By this arrangement it is also possible to adjust the position of the peeler blade without removing the cover plate 82 or otherwise dismantling the pump. This is accomplished by first loosening the retaining set screw 105 and then turning the adjusting shaft 115 until the sharpened lower end of the bar is brought into engagement with the periph- ,ery of the impeller 29. The peeler blade is then elevated or backed off somewhat by turning the shaft 115 in the other direction just enough to lift it out of contact with the impeller periphery, as may be ascertained by turning the impeller to see that it does not rub on the blade. The blade is then locked in position by tightening the set screw 105 together with its lock nut 106 and by tightening the lock nut 118 on the adjusting shaft 115 as previously explained. This embodiment of the invention constitutes the subject matter of Divisional Application Serial No. 627,721 filed November 2l, 1956.

From the foregoing description and explanation of the operation of the improved self-priming centrifugal pump herein set forth, it is apparent that there has been provided by the present invention a new centrifugal pump of compact unitary and rugged construction that is provided with an improved adjustable peeler arrangement adapted to enhance its self-priming qualities.

Although only a few modifications of a specific embodiment of the invention have been described in illustrating improved apparatus for practicing the present invention, it is to be understood that the improved pump herein set forth constitutes a particular exemplifcation of the invention, and that the structures shown may be changed and modified without departing from the spirit and scope of the invention as defined in the subjoined claims.

Having now been fully described, the invention is hereby claimed as follows:

1. In a centrifugal pump, a unitary casing constituting an impeller chamber with an integrally formed priming water chamber superimposed thereon and interconnected therewith by a discharge passage disposed vertically in tangential relationship with said impeller chamber and an adjacent priming water passage disposed vertically in parallel circumferentially spaced relationship with said discharge passage together with an integrally formed intake chamber arranged coaxially of said impeller chamber and interconnected therewith by a coaxial inlet port, said casing presenting an impeller-admitting opening at the side of said impeller chamber opposite from said inlet port and presenting a shaft receiving opening at the side of said intake chamber opposite from said interconnecting inlet port, there being an intake passage 'disposed slib-l stantially tangentially of said intake chamber, an impeller disposed within said impeller chamber, a shaft secured to said impeller and extending therefrom through said inlet port and said shaft receiving opening for rotating said impeller to draw in liquid through said inlet port and discharge it through said discharge passage, a sealing gland engaging said shaft at said shaft receiving opening to prevent leakage through said opening along said shaft, said gland being subjected to the suction action of said impeller, a vertically disposed bar constituting a renew. able peeler movably mounted in said casing between said discharge passage and said priming water passage, said bar presenting a pointed peeler at its lower end disposed adjacent to the periphery of said impeller in position to divert liquid therefrom into said tangential discharge passage and adjustable relative to said impeller periphery by movement in said casing, securing means mounted in and extending through said casing in position to engage and secure said peeler in adjusted relationship with said impeller, and a cover plate secured to said casing in position to cover both said impeller admitting opening and said securing means for said peeler.

2. In a centrifugal pump, a unitary housing constituting an impeller casing presenting a faced opening for receiving a pump impeller and having formed therein a discharging passage, an impeller rotatably mounted within said casing and operative to eject liquid through said discharging passage, a removable and replaceable peeler bar pivotally mounted within said housing in vertical position to constitute part of one side of said discharging passage and to be movable for pivotally adjusting the position of the lower end thereof relative to the periphery 'of said impeller for diverting liquid therefrom into said discharging passage, a set screw threaded through the faced portion lof said housing adjacent to` said impeller receiving opening in position to engage said peeler to retain it in adjusted position relative to said impeller, and a cover plate disposed to engage the faced portion of said housing around said opening to close it for completing said impeller chamber and serving also to cover said set screw for protecting it.

3. In a centrifugal pump, a casing constituting a working chamber for receiving an impeller and a superimposed integrally formed priming water chamber, said chambers being interconnected by a vertical discharge passage disposed tangentially |of said working chamber and an adjacent vertical priming water passage disposed in circumferentially spaced parallel relationship with said discharge passage, a peeler pivot disposed within said casing between said discharge passage and said adjacent priming water passage, a peeler in the form of a vertically disposed renewable bar pivotally suspended from said pivot and depending therefrom between said discharge passage and said adjacent priming water passage with its lower end in position to cooperate with the periphery lof an impeller in said working chamber, and retaining means operative from the exterior tof said casing and arranged to secure said pivotally depending peeler in adjusted position to constitute a separating guide vane between said discharge passage and said priming water passage for diverting water from the impeller into said discharge passage.

4. In a centrifugal pump, a unitary casing constituting an impeller chamber with an integrally formed priming water chamber superimposed thereon and interconnected therewith by means of a discharge passage disposed vertically in tangential relationship with said impeller chamber and an adjacent priming water passage disposed vertically in parallel circumferentially spaced relationship with said discharge passage said casing presenting an impeller receiving opening, an impeller disposed within said impeller chamber for rotation therein to eject liquid through said discharge passage, a pivot stud mounted in said casing between said discharge passage and said adjacent primingtpassage. apeeler pivotally suspended from said pivot stud in position to define part Vof one side of saiddischarge passage with its pointed ylower end adjacent to the periphery 'of said irnpeller and adjustable relative thereto by pivoting movement about said pivot stud, securing means extending through said casing and arranged to engage saidpeeler near its lower end to secure it in adjusted position relative to the periphery of said ilmpeller, and a cover plate secured to said casing in position to cover said impeller receiving opening to enclose said irnpeller and at the same time to cover said peeler securing means to prevent leakage at the point Where said means passes through said casing.

References Cited ,in the le vof this patent UNrTED STATES PATENT-s Longenecker Jan. 22, 1935 Teel Mar. 30, 1937 La Bour June 3, 1941 La -Bour Aug. 11, 1942 Browne Feb. 15, 1944 Robinson Mar. 27, 1945 Longenecker May 15, 1945 Longenecker Aug. 7, 1945 Longeneclcer Oct. 9, 1945 Nelson May 14, 1946 

